Ion exchange resins derived from vinyl pyridine, polyvinyl benzene and styrene compounds



ION EXCHANGE RESINS DERIVED FROM VINYL PYRIDINE, POLYVINYLBENZENE ANDSTYRENE COMPQUNDS Yoshiaki Murata, Los Angeles, Calif., assignor toNational Aluminate Corporation, Chicago, EL, 2 corporation of DelawareNo Drawing. Application August 4, 1953 Serial No. 372,391

17 Claims. Ci.260.-2.1)

It has been known heretofore the quaternary amine nitrogen atoms havethe ability of exchanging anions in saline aqueous solutions, but thequaternary amino groups in most quaternary amine compounds are sohydrophilic that they render the entire compound soluble in water andhence are of no value for extracting anions from the water. 4

One of the objects of the inventionis to provide a "nited States PatentOT 2,828,270 Patented Mar. 25, 1 958 percent of a styrene, such asstyrene itself, dischlorostyrene and alpha-methylstyrene, about 19 to 66molar percent of a vinyl pyridine, such as 2-vinyl pyridine, 4- vinylpyridine, and their homologues, an'd about 1.3 to 12 molar'percent of apolyvinylbenzene, such as the divinyl and trivinyl benzenes.

In the alkylation of the copolymer to form a quaternary ammonium resin,the molar concentration of the alkylatingagent is preferably equal to orgreater than the molar concentration of the vinyl pyridine in the resin.

, Excellent results were obtained with methyl iodide as the alk'ylatingagent. Other alkylating agents are dimethyl sulfate, diethyl sulfate,methyl chloride, ethyl chloride, methyl bromide and other lower alkylhalides containing less than six carbon atoms. r Moderate temperature'sfrom room temperature 7 degrees C.) to 100 degrees C.are suflicient toeifect the water insoluble resin containmgquaternary amine groups.

Another object is to provide ainew process forremoving anions fromwater. inafter.

Other objects will appearhere In accordance with the invention, newquaternary salts and hydroxides of new heteropolymers of a vinylpyridine,

a styrene and a polyvinylbenzene have been prepared.

These products were prepared; by copolymerizing a vinyl pyridine withstyrene or afsubstituted styrene and a hydroxides were preparedbyreacting theresultantproduct with a base, e. g., sodium hydroxide,lithium hydroxide, potassium hydroxide, etc.

polymerization and alkylation reactions. I

The following examples illustrate different methods of preparing thecopolymers as well as different types. of

compounds falling within the scope of the invention but are not intendedto limit the broader aspects of the invention.

The charge was placed in a 250 ml. Erlenmeyer flask. The flask wasstoppered and the solution was reacted at room temperature for 17 hours.The soft gel was reacted further in a hot water bath (70 to 80 degreesC.) for S hours. The hard gel was broken up and dried in the oven at 250degrees F. for 18 hours. The dried resin was-ground and screened (l2+30mesh).

The resin was methylated in a 250 ml. Erlenmeyer flask with 35 grams ofmethyl iodide at room temperature for 72 hours. The resin was dried at210 degrees F. for 3 hours. The quaternary amine exchange capacity was'then determined and found to be between 6,000 and The copolymeri'zationcan be effected with or without" a catalyst. If no catalyst isused,however,.a non-uniformproduct results. 'It is preferable, therefore, touse a polymerization catalyst, for example, benzoyl peroxide,

'cumene hydroperoxide, or other peroxide catalyst.

The physical properties of the resin will vary depending vinyl pyridineresults in resins having low ion exchanging capacities. ,Lowconcentrations of polyvinylbenzene produce thermoplastic resins.Concentrations of peroxide catalyst above 0.2% by weight of thereactants result in a thermoplastic resin.

It has been found that, certain proportions of the.

7,000 grains per cubic foot.

' EXAMPLE II Suspensionpolymerization Charge:

0.5% solution.

The polyvinyl alcohol solution and water were placed in a 1 liter,-3-necked, round-bottom flask equipped with 1 a reflux condenser, 21stirrer, and a thermometer. Styrene,

components are required for the production of a resin which when in thequaternary amine form is suitable for use as an anion exchange resin,having the requisite ion sistance to heat. Thus, a resin which is auseful anion ex changer in the quaternary amine form is prepared by co-L polymerizing the components in proportions that provide in thereactants and in the resin about 30 to 78 molar 2-vinylpyridine,divinylbenzene, and benzoyl perom'de mixture were added and the mixturewas stirred at a moderate speed, and reacted at 50 degrees C. for 3hours. The temperature was then raised to to degrees C. and reacted; atthis temperature for 3 hours. The beads were poured intojafbeaker,treated with dilute hydrochloric acid, filtered, washed with water, anddried at 60 to 70 degrees C. for 1 71lio'ur's; The beads were thentreated with sodium carbonate solution, filtered, washed with water andredried at degrees C. for 17 hours.

The driedbeads'were. methylated in a 250 ml. Erlenmeyer flask withmethyl iodide (25 grams) at room temperature for 6 hours, then dried at100 degrees C. for 2 hours. :The ion" exchange capacity was determinedand ,0 found to be around 3400 grains per cubic foot.

EXAMPLE III degrees .C. for :5 hours? The resulting beads were filteredg V 4 the basic resin and 250 ml. of wash water followed. The water fromthe sodium chloride solution and the wash Water were collected and thealkalinity of the water was titrated with standard acid. This resin hada capacity of a 2,900 grains per eubic'foot of exchanging anioncalculated as CaCO EXAMPLE IV Forty (40) grams of 2-vinyl pyridine, 52grams of styrene, 20 grams of divinylbenzene (18%) and 0.1% benzoylperoxide were polymerized at room temperature for 204 hours. Theresulting resin was broken up and methylated with 30 grams of methyliodide at room temperature for 17 hours. Theresulting product whenconverted to the alkaline form as in Example III and treated 'withthe'brine solution had a capacity of 7,000 grains per cubic foot as CaCOV The following tables illustrate the results obtained in preparingcopolymers and quaternary salts thereof from various reactants undervarying conditions. In Table II the products corresponding to ExamplesXVII to XXIV were not converted to quaternary salts since they were toosoft or had physical properties not suitable for 'ionv exchange. I

TABLE I.VBIULK BOLYMIERIZATION I Divinyl- ConditionofExp. Drying2-Vinyl- Styrene, Benzene Benzoyl Physical Example No. Pyridine, gm.(18%), Peroxide, Property gm. gm. gm. Temp., Time, Temp., Time,

' 0. hr. F. hr.

' A 7 2e s2 10 0.1 70-s0 2 gel.

12 45 15 0.1- 80 Do. 1a 52 25 0.1 Do. 1a. 52 25 0.1 2 hard red 18 resm.13 52 12.5 0.1 6 180 1 Do. 17.5 52 20 0.1 g 230 11 Do. 20 52 40 0.2 g250 18 Do. 13 52 0.1 200 18 Do. 13 a2 25 0.1 g 240 V 24 Do. 20 52 25 V0.1 240 24 Do. 52 20 0.1 204 D0. so 52 22 1.0 gig f; Do.

72 240 24 soft; V 14 214 17 resin. 5 52 22 a: a nonuni- 53 52 1 '22 "0.0.72 L 24 form 33 $13 21 a e so 52 '2 14 214, -17 resin XXI".-. 52 22 1.0Z2 gig f; 'Do. xxn------ s2 10 1.0 {2 gig f; Do. xxm.-. as 52 10 1.0 gigf5, Do. I nonuni- XXIV 53 20 10 0.0 72 24 form v V V V 14 214 17 mmTABLE II Product Reaction Time Drying of Methyl Physical Property afterCapacity, Example No. Example Iodide, treat. with NaOH gin/ ties No. gm.Temp., Time, Temp., Time, 800:

0. hr. F. In.

10 210 5 swells m Hi0 color throw. 3 170 Slightly soft, color throw. 1,6 180 72 swelled and soft 1, 615 17 17 50% expansion- 5,000 17 170 1750% expansion 3, 630 1% '200 18 d0 4,500 2% 7220 20 Little expansion, h3, 400 1% 210 80 No expansion, hard- 3, 400 1% 220 3 0-...;..--- 2,800 1,5 220 3 o 4,000 17 Little expansion... 7, 000 17 212 4' Swelled,oolorthrow- TABLE I11.'--SEISPEN$ION ronmnrzarrou Reaction Drying Dichlo'ro'-2-vinyl Dlvlnyl Benzoyl i Example No. Styren Styrene, Pyridine; BenzenePeroxide, Physical gm. gm. gm. (18%), gm. gm. Temp, Time, Temp. Time,Properties 0. hr. 0. Hr.

30 10 5 8 1 130 2 Granular a v p resin. 4 30 10 1. 30-80 6 60-70 24Hard; brown beads. 30 10 2 30-80 6 60-70 24: l6 5 1 65-75 6 80 72 Beads.26. 5 7 1 75 7 80 72 D0. 25 10 .1 75 6 D0. 26. 5 7 1 75 6 80 72 Do. 26.57 .1 40 2 60 72 Do. 28 5 .1 50 18 D0. 20 5 .1 50-80 5 90 I 17 D0. 30 20(40%) .6 80 100 17 D0. 20 10 (40%) 1 80 15 100 17 D0.

TABLE IV Drying r Product Capacity, Physical Example No. of Mel, gr. itProperty Example gm. Temp., 'Time, as [1.003

No. 0. hr.

XLIX XL"... 3, 435 Hard, heavy resin. L XLVI--. 2, 900 Hard.

Alpha methyl styrene and other polymerizablehomologues may be usedinstead of the styrene or dichlorostyr'ene in the foregoing examples solong as" the substituent groups other than the vinyl group are inert.The products made from dichlorostyrene were heavier and had betterphysical properties than those obtained from styrene.

Instead of Z-Vinylpyridine, isomers and homologues thereof and of theisomers may be used in making the copolymers. Trivinylbenzene may beemployed in place of divinylbenzene.

Quaternary amine compounds are unstable to heat, especially in thehydroxyl form, but even the chloride or sulphate salts should not beheated above 150 degrees C. for any extended period. The hydroxyl formof the resin should not be heated above about 60 degrees C. for any longperiods, since the quaternary group Will break down.

An advantage of the present product is that the quaternary amine groupsare such strong bases that upon being converted to the hydroxyl form bysodium hydroxide or any other strong alkali metal hydroxide a strongbase results which will remove chloride ions from a dilute solution ofsodium chloride replacing them with hydroxyl ions. This makes itpossible to remove the anion from an aqueous solution first and thecations afterwards. This is especially efficacious where the salts arebeing removed from a product such as sugar which will hydrolyze in thepresence of hydrogen ion.

A further advantage of these products in their alkaline form is thatthey can act as basic catalysts where the base is in a captive form.That is, it is tied to the solid granules and cannot diffuse through thereaction media. When the reaction is completed the catalyst can be re- 7moved by merely filtering the catalyst from the reaction zone. Such aprocedure has a great advantage over the common practice where thecatalyst must be neutralized with acid and finally the product must bedistilled or extracted from the resulting salt solution.

The invention is hereby claimed as follows:

1. A water-insoluble resinous composition from the 2. A waterrinsolublelower alkyl quaternary ammonium salt of a hard resinous copolymer offrom 19 to 66 molar percent of 2-vinyl pyridine, "from 1.3 to 12' molarpercent of divinylbenzene and from 30 to 78 molar percent of styrene.

3. A water-insoluble lower alkyl quaternary ammcnium hydroxide of a hardresinous copolymer of from 19 to 66 molar percentof 2-vinyl pyridine,from 1.3 to

12 molar percent of divinylbenzene and from 30 to 78 molar percent ofstyrene.

4. A water-insoluble lower alkyl quaternary ammonium salt of a hardresinous copolymer of from 19 to 66 molar percent of 2-vinyl pyridine,from 1.3 to 12 molar percent of divinylbenzene and from 30 to 78 molarpercent of dichlorostyrene.

5. A water-insoluble lower alkyl quaternary ammonium hydroxide of a hardresinous copolymer of from 19 to 66 molar percent of 2-vinyl pyridine,from 1.3 to 12 molar percent of divinylbenzene and from 30 to 78 molarpercent of dichlorostyrene.

6. A water-insoluble lower alkyl quaternary ammonium salt of a hardresinous copolymer of from 19 to 66 molar percent of 2-vinyl pyridine,from 1.3 to 12 molar percent of divinylbenzene and from 30 to 78 molarpercent of alpha-methylstyrene.

7. A water-insoluble lower alkyl quaternary ammonium hydroxide of a hardresinous copolymer of from 19 to 66 molar percent of 2-vinyl pyridine,from 1.3 to 12 molar percent of divinylbenzene and from '30 to 78 molarpercent of alpha-methylstyrene.

8. An anion exchange resin consisting essentially of a water-insolublemethyl iodide quaternary ammonium salt of a hard resinous copolymer offrom 19 to 66 molar percent of 2-vinyl pyridine, from 1.3 to 12 molarpercent of divinylbenzene and from 30 to 78 molar percent of styrene.

9. An anion exchange resin consisting essentially of a water-insolublemethyl iodide quaternary ammonium salt of a hard resinous copolymer offrom 19 to 66 molar percent of 2-vinyl pyridine, from 1.3 to 12 molarpercent of divinylbenzene and from 30 to 78 molar percent of digroupconsisting of the lower alkyl quaternary ammonium 70 salts andhydroxides of a copolymer of from 19 to 66 chlorostyremlf' molar percentof vinyl pyridine, from 1.3 t 12 molar 10. An anion exchange resinconsisting essent1ally of a percent f polyvinylbenzene and f 30 to 7molar water-insoluble methyl quaternary ammonium hydroxide ercent of acompound from the group consisting of Of a hard I'GSlIlOlJS copolymer Offl'OlIl 19130 66 1110181 perstyrene, dichlorostyrene andalpha-methylstyrene. 15 cent of 2-vinyl pyridine, from 1.3 to 12 molarpercent of styrene.

divinylbenzene and from 30 to 78 molartpercent ofii 11. An anionexchange resin consisting essentially of a water-insoluble methylquaternary ammonium hye droxide of a hard'resinous copolymer of from 19to 66 molar percent of 2-vinyl pyridine, from 1.3 to 12 molar dine-,fromlfi to 12 molar percentof divinylbenzene and from 30 to 78 molar percentof dichlorostyrene. Y

15. A method of removing anions from a solution containing thesame-.which comprises bringing said solution percent of divinylbenzeneand from 30 to 78 molar percent of dichlorostyrene. V r

12. A method of removing anions from a solution containing the samewhich comprises bringing said solution into contact with a resinouswater-insoluble lower alkyl quaternary ammonium compound of a hardresinous copolymer of from 19 to 66 molar percent of vinyl pyridine,from 1.3 to 12 molar percent of polyvinylbenzene and from 30 to 78 molarpercent of a compound from the group consisting ofstyrene,dichlorostyrene and alphamethylstyrene. s

13. A method of removing anions from a solution containing the samewhich comprises bringing said solutioninto contact with a resinouswater-insoluble methyl quaternary ammonium compound of a hard resinouscopolymer of from 19 to 66 molar percent of vinyl pyridine;

- from 1.3 to 12 molar percent of polyvinylbenzene and from 30 to 78molar percent of a compound from the group consisting of styrene,dichlorostyrene and alphamethylstyrene. 7

16. A method of removing anions from a solution containing the samewhich comprises bringing said solution 4 into contact with a resinouswater-insoluble methyl qua ternary ammonium hydroxide of a hardresinouscopolymer of from 19 066 molar percent of 2-viny1 pyridine, from 1,3 to12 molar percent of divinylbenzene and from to 78 molar percent ofstyrene.

17. A method of removing anions from a solution containing the samewhich comprises bringing said solution into contact with a resinouswater-insoluble methyl quaternary ammonium hydroxide of a hard resinouscopolymer of from 19 to 66 molar percent of 2-vinyl pyridine, from 1.3to 12 molar percent of divinylbenzene and from 30 to 78 molar percent ofdichlorostyrene.

References Cited in the, file of this patent V,

UNITED STATES PATENTS Jackson Feb. 6, 1951 Jackson Feb. 6, 1951

1. A WATER-INSOLUBLE RESINOUS COMPOSITION FROM THE GROUP CONSISTING OFTHE LOWER ALKYL QUATERNARY AMMONIUM SALTS AND HYDROXIDES OF A COPOLYMEROF FROM 19 TO 66 MOLAR PERCENT OF VINYL PYRIDINE, FROM 1.3 TO 12 MOLARPERCENT OF POLYVINYLBENZENE AND FROM 30 TO 78 MOLAR PERCENT OF ACOMPOUND FROM THE GROUP CONSISTING OF STYRENE, DICHLOROSTYRENE ANDALPHA-METHYLSTYRENE.